Research provides new insights into diabetic retinopathy risk

People with diabetes could reduce their risk of diabetic retinopathy for every hour they achieve target blood glucose levels, research suggests.

Chinese researchers reported the association following a study of 3,262 people with type 2 diabetes. A total of 780 people in the study had diabetic retinopathy before it began. 

On average, the participants were aged 60 years and had elevated average HbA1c readings of 74 mmol/mol (8.9%). 

They wore continuous glucose monitors for a three-day period and had their time measured in real time for how often their blood glucose was within a target range of 3.9-10 mmol/l.

Those whose typical 24-hour readings were in range the least amount of time were more likely to have retinopathy. The less time spent being in range was also associated with increased eye damage among those with retinopathy. 

Significantly, the association between time in range and retinopathy was separate from HbA1c, indicating that people who had good control over a three-month period could still do damage with fluctuations.

“To minimise the risk of retinopathy, a patient needs to control his/her blood glucose as soon as possible, and maintain the glucose levels in the target range as long as possible,” said study author Dr Weiping Jia, who works at the Shanghai Jiao Tong University Affiliated Sixth People’s Hospital.

While only an association was observed, and the study was not designed to show whether time spent in blood glucose target range could impact retinopathy risk, the results add further credence to the importance of managing blood glucose levels to reduce complications risk. 

Commenting on the research, Dr. Roy Beck, executive director of the Jaeb Center for Health Research in Tampa, Florida, who wasn’t involved in the study, said: “The closer to the normal range a person with diabetes can achieve, the lower will be the risk of retinopathy. If near normal glucose levels can be achieved, the risk is very low.”